$\large\frac{3\cos\theta+\cos 3\theta}{3\sin \theta-\sin 3\theta}$ is equal to

Question

$\begin{array}{1 1}(a)\;1+\cot^2\theta&(b)\;\cot^4\theta\\(c)\;\cot^3\theta&(d)\;2\cot\theta\end{array}$